Welcome to the AC Tropical Fish aquarium forum. Our aquarium forum is the place to discuss any aquarium related issue in a friendly environment. Our aquarium forum welcomes aquarists of all levels from beginners to experts. Please ask a question in the how to section of our forum or read the FAQ section if you have any questions. register to and become a part of our friendly aquarium forum community today.

One overly aggressive tiger barb

0

I have had my tank up for about nine month. I started with five tigers (I know everyone will probably say it is not enough but that is what I was told was the minimum when I first was looking), two regular and three green. I also got three cherry barbs, a rainbow shark and a bristlenose pleco. I lost a few tigers and some other fish over time, as far as I know it was due to water quality, but I replaced them and things were fine for a time. I had never seen the tigers being aggressive towards any of the others, the rainbow was the main one chasing everything around. I know the cherries maybe should not be with the tigers but I have not seen them have a problem with the tigers. After losing two tigers a while back I waited a few months to buy more.

Once I knew the tank was stable (after changing to a soil substrate) I purchased two more tigers, one regular and one green, both being at least half the size of the older ones. I noticed the new regular tiger hanging out around one of the older ones a lot and thought it was kind of odd but never thought about it further. About two weeks later I noticed a cherry had died, I did not look at it to see if there was any damage to it, but now I wish I would have. I took a second look at what the new tiger was doing around the older ones and it was nipping at their lower fins, some of them have damage to their fins, but the older ones just swam away, they don't chase him off even though they are bigger. I have not seen the new tiger chasing the cherries but I suspect it may have caused the death of the one cherry, water parameters were good when he died (0 ppm ammonia and nitrites and 5-10 ppm nitrates). Up until now the tiger cherry mix has not been a problem, there was three tigers and three cherries for many months, nor has the number of tigers been a problem, as far as I could tell.

Is this new tiger just overly aggressive, especially towards the other tigers or are my other tigers just not very aggressive? I was thinking about trying to go back to the store and see if they can swap it out. Is there anything else that I can do to put him in his place since the other tigers wont?

First of all how big is the tank? Usually aggression is the result of not having enough of the species, but first we need to know what size of tank you're working with, because some of the fish you've listed require pretty large tanks anyway.

Five is a very small number when it comes to schooling fish that nip. The reason you want to have a larger school is that then the aggressive behavior is spread around to multiple specimens. The behavior doesn't really go away, because Tiger Barbs (and some other fish) have a pecking order. Your new one, is behaving as the dominant fish in the shoal, and doesn't really have a large enough group to spread his attentions around, and has such a small group he has plenty of time to worry about every single one. There is likely to always be a dominant fish because that's the normal behavior.

I'd suggest if you like the barbs you double the size of your school you have now. Yes it seems counter intuitive.

A community aquarium is just that, a community. While one fish may be displaying unhealthy behaviors, this is often a symptom of imbalance within the community as a whole, rather than a single bad apple. I haven't kept either tiger barbs or the shark myself, but I'm guessing things would work better without the shark.

Yes five tigers is what I currently have. I just wonder why nipping is an issue this time. When I had five tigers previously they would chase each other around some but I never saw deliberate nipping like this. When there were three tigers for a few months I noticed less chasing around that the barbs did, mainly the rainbow chased but only to chase them away I never saw him actually nip at them.

Honestly fish are animals their all different, I have 4 gold honey gouramis in my 55. They all are super peaceful but one male that like to chase my cardinals. So you just happen to get a very aggressive tiger. The only solution is to A get more tigers or B get rid of him. I know this is probably not what you want to hear but this is the only way to solve your problem.

One thing to note about the haven't seen it before side of behaviors is that we tend to buy immature fish from the store, but they might be at various stages of maturity. And with that maturity comes reproductive behaviors such as the desire to be more territorial, or show dominance.